The brachial artery (a. brachialis) is a continuation of the axillary artery. It begins at the level of the lower edge of the pectoralis major muscle and here lies in front of the coracobrachialis muscle.
The axillary artery (a. axillaris) is a continuation of the subclavian artery (from the level of the 1st rib). It is located deep in the axillary fossa and is surrounded by the trunks of the brachial plexus.
The internal carotid artery (a.carotis interna) supplies the brain and the organ of vision. The internal carotid artery has cervical, petrous, cavernous and cerebral parts. This artery does not give off branches on the neck.
The external carotid artery (a.carotis externa) is one of the two terminal branches of the common carotid artery. It separates from the common carotid artery within the carotid triangle at the level of the upper edge of the thyroid cartilage.
From the aortic arch, the brachiocephalic trunk, the left common carotid artery, and the left subclavian artery branch off in sequence, carrying blood to the head and neck, upper limbs, and the anterior wall of the chest and abdomen.
The aorta is the largest unpaired arterial vessel of the systemic circulation. The aorta is divided into three sections: the ascending aorta, the aortic arch, and the descending aorta, which in turn is divided into the thoracic and abdominal sections.
Venules begin from the capillaries of the lungs, which merge into larger veins and form two pulmonary veins in each lung. Of the two right pulmonary veins, the upper one has a larger diameter, since it carries blood from two lobes of the right lung (upper and middle). Of the two left pulmonary veins, the lower vein has a larger diameter.
The pulmonary trunk (truncus pulmonalis) with a diameter of 30 mm emerges from the right ventricle of the heart, from which it is separated by its valve. The beginning of the pulmonary trunk and, accordingly, its opening are projected onto the anterior chest wall above the place of attachment of the cartilage of the third left rib to the sternum.
The pericardium (pericardial sac) separates the heart from neighboring organs and is a thin and at the same time dense, strong fibrous-serous sac in which the heart is located.
